This 9ct 2 colour spinner wedding ring came to me to rejoin it after it had been sawn off the finger. I soldered the inside (yellow gold) section and rounded and cleaned it up, then filed a v shape in the outer (white gold) section at the join, then fitted it in place. The v shape (shown near the beginning of the video) is to allow me to weld it all the way through so it became strong.
The ring is very thin which means I could only use a low powered weld. This makes it more difficult than being able to just 'blast it' because thin metal retreats away from the welding area as it melts. It's easy to blow a hole in it, which would be difficult to fill. As you can probably tell, it was more of a struggle to weld than usual and I had to be careful at the edges, not to join it to the yellow gold section's outer rim. You might notice that the end of the electrode is slightly rounded in the first part of the video, which makes it difficult to weld compared to a more pointed one. This was silly of me and I soon had to change it to get a better weld - the lesson here is : don't be lazy with changing electrodes.
At first my Lampert PUK3S was in GAP mode at 5ms 20% power and when I had built it up a little I increased it to 6ms 25%.